Valencene and nootkatone are sesquiterpenes that occur in essential oils, such as citrus oils, including orange and grapefruit. Valencene is produced by cyclization of the acyclic pyrophosphate terpene precursor farnesyl diphosphate (FPP), and oxidation of valencene results in the formation of nootkatone. Valencene and nootkatone are both used in the perfume and flavor industry.
Valencene originally was extracted from the peel of the Valencia orange and nootkatone is extracted from grapefruit peels or produced by oxidation of extracted valencene. Although chemical approaches to generate valencene and nootkatone have been attempted, the highly complex structures of these compounds have rendered economically viable synthetic processes for their preparation in large quantities unattainable. Valencene has been produced in host cells catalyzed by nucleic acid encoding a citrus valencene synthase (see, e.g., U.S. Pat. No. 7,442,785). Improvements in production and alternative means of production and production of valencene and other terpenes are sought.
Thus, among the objects herein, is the provision of valencene synthase polypeptides and methods for production of terpene products whose production is catalyzed by the polypeptides.